Referring to FIG. 1, a typical camera 1 comprises three essential parts, i.e. a main body 11, a lens unit 12 and an image-forming unit (not shown). The lens set 12 comprises a plurality of delicate lens disposed in the front of the main body 11. By means of the lens set 12, the light reflected from a photographed object 2 is focused on the image-forming unit for exposure. For example, the image-forming unit can be a film for a film-type camera or a charge-coupled device (CCD) for a digital still camera.
As is understood, the definition of a photograph taken by a camera is largely effected by the focusing operation of the camera. The object distance should be within an acceptable focusing area of the camera, and the camera should be stabilized to well perform the focusing operation.
When the focusing range, i.e. the object distance d between the camera 1 and the object 2, is very short, for example 20˜100 mm, the definition ranges of a photograph varying with distances are shown in FIG. 2. In general, an effective focusing operation is done when a definition of at least 80% is achieved. Curves a and b show two photographing conditions where focusing distances are 70 mm and 30 mm, respectively. For Curve a where the object distance d is 70 mm, the allowable deviation for more than 80% definition is as narrow as within the range A. Once the object distance d is reduced to 30 mm, the even sharp curve b is rendered. In this case, the allowable deviation for more than 80% definition is as indicated by the range B, which is as narrow as several millimeters. Therefore, it is likely to result in an obscure photo image even if just a little vibration of the camera is done.
Conventionally, a tripod is used to improve the rocking problem, as shown in FIG. 3. The camera 1 is supported onto the top of the tripod 3 so as to exempt from being held with hands. The use of the tripod 3, however, is accompanied with undesired cumbersome, weighty and costly problems. Since the tripod 3 generally has height greater than a certain level, the photographed object 2 needs to be put on a raised platform 4 when a close-up shot is to be taken. Unfortunately, in some situations or locations, it is preferred not to move the object, e.g. when a little bug resting on the grass is to be photographed. Moreover, it is sometimes hard to find a suitable place for the tripod to stand.